Do Series A singles have sumping problems?

[vincenttwin]

Had the conways valve on my A and B. For many years never a promblem. With it I know of only one bike that it would suck open on but that bike had a worn out pump on the suck side
Also it's brass and looks Like it belongs on a A
Nice bit of kit better than a tap you could forget . But I always check my oil return on the first start of the day
Happyriding
Peter

 

[vincenttwin]

Might to say would not suck open on

 

[A_HRD]

Yes, lots of people use the Conways valve on their Series A. Properly primed it seems to work well. There is one on Nigel - The Club Series A Comet. But I currently have the oil-pump off it at the moment to investigate a reported 'failure to return oil' problem; it fills the sump instead. A slightly different scenario to the one highlighted by b'knighted above, I agree.

Coincidently, I also have my own 'A' oil-pump on the bench at the moment and 2 thoroughly worn-out ones belonging to a mate. All exhibit much the same problems to varying degrees - worn gears, worn shafts, worn OP10 intermediate plate and far too much end float on the gears. Nigel has 10-12 thou rather than the recommended 2 thou end-float. They are pretty simple devices and if the late Bob Stafford's writings are carefully followed, the engine shouldn't 'sump' at all - or at least not excessively.

http://www.voc.uk.com/net/docs/4.1/4.1-382-48.pdf (or find it in MPH 382)

The only bit where I deviate from Bob's practice is to flatten-down the mating faces of the pump until there is ZERO end-float (or even a thou or two of gear standing proud) and then insert a very thin (~about 3 thou) gasket between face and steel plate - the gasket made from a brown coloured "baking paper" available in the UK. A little Wellseal keeps it all oil-tight.

Peter B
Bristol, UK.
WANTED: Series 'A' Front Frame.

 

[nkt267]

I did see a letter somewhere recently,not on this forum, where a Norton kept sumping really badly..When the owner finally tracked the fault it was due to a cracked oil return tube inside the oil tank. The sump was filling from the return side..John

 

[b'knighted]

Thank you all for the advice. Especially the advice on bleeding and priming. I'll probably be asking more questions about this once I've tried fitting a flexible pipe.

I didn't know that the Conways valve was originally designed for 'A's or I not have asked the question.

I have looked up some of Bob Stafford's writings but can never be sure I've found all the relevant articles.

I'll try to finish my fettling and get the bike on the road for the summer without stripping off too many more bits, and certainly without breaking any more.

 

[b'knighted]

I've been fiddling again.

Having sorted out what I want to do for the feed pipe I decided that it would be clever to modify the feed banjo bolt on the top front of the oil pump. My idea was to drill and tap it like the drain banjo bolts available for post-war bikes so that I could pump priming oil into the pump and possibly suck oil down through the anti drain valve to fill the feed pipe. As I looked at the bits and pieces I saw that the rear top banjo bolt, pressure feed to the engine?, was already tapped and plugged with an Allen screw and locknut.
Is this standard or in any way common, or does it sound as if the previous owner has already modified it to facilitate priming?

I've removed the oil tank to wash it out and now wonder whether the recommendations for the next fill of oil are the same as for post-war bikes or whether the original mono-grade recommendations should be followed with As?

 

[Pete Appleton]

I saw that the rear top banjo bolt, pressure feed to the engine?, was already tapped and plugged with an Allen screw and locknut.

That is the adjustment for the cylinder oil feed. 15 to 20 drips per minute. Have a look at the series A section in Richardson.

 

[b'knighted]

Thank you.

 

[Monkeypants]

My Norton 650ss fills the sump after about a month of sitting, then starts to leak profusely from the top of the crankcase. I have looked at the anti sump ball valve with ignition cutout, but it still seemed a bit risky should the switch fail and allow the engine to run without first having the oil supply turned on.
The plan is to make a valve which uses the 650SS igntion key as handle. When the valve is in the on position, the key can be removed, when the valve is in the off position the key cannot be removed from the valve. I only have two keys for the bike and only ever use the one, as the spare is taped solidly onto the bike in hidden spot, so I think this antisump valve will be without risk. All the bits for it are in a small box, the machining is mostly done, just need a bit of time to complete it.
Glen

 

[Monkeypants]

and of course most Vincents do not have key ignitions, but for those that do have them fitted, a possibility?
Glen